Engine Sludge;FYI 2003 V.W. Passat 1.8t 116,xxx miles and regular synthetic oil changes (5/40)

whats the best method for curing and removing this problem (FYI 2003 V.W. Passat 1.8t [common problem with sludge according to research including class action lawsuit]) < IDC about that but the shop that has it wants $2,200 dollars to replace this-and-that to fix low oil pressure in the head, (cough Bull$hit i say) the cars worth is $3,xxx. does anyone have advice or expertise in this area???